Equilibrium Constants
Mostrando 1-12 de 393 artigos, teses e dissertações.
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1. New nonlinear solution of nearly incompressible hyperelastic FGM cylindrical shells with arbitrary variable thickness and non-uniform pressure based on perturbation theory
Abstract In this paper, nonlinear analysis of thick cylindrical shells with arbitrary variable thickness made of hyperelastic FGM with radially variation of material properties in nearly incompressible state under non-uniform pressure loading is presented. Thickness and pressure of the shell vary in axial direction by linear and/or nonlinear functions. The g
Lat. Am. j. solids struct.. Publicado em: 28/10/2019
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2. ESPECIAÇÃO DINÂMICA DE METAIS TRAÇO EM AMBIENTE AQUÁTICO USANDO CRONOPOTENCIOMETRIA DE REDISSOLUÇÃO ANÓDICA
The contamination of natural environments by trace metals has several adverse effects on human health, which is mainly due to the high toxicity, persistence and reactivity of these species in the environment. To understand the bioavailability of trace metals, it is necessary to know the speciation in equilibrium and the dynamic behavior of the system. In thi
Quím. Nova. Publicado em: 2018-07
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3. EQUILÍBRIO QUÍMICO E CINÉTICA ENZIMÁTICA DA INTERAÇÃO DE α-AMILASE COM COMPOSTOS FENÓLICOS ENCONTRADOS EM CERVEJA
α-amylase is a key enzyme in the production of beer due to the breakdown of starch into fermentable sugars. During the preparation of the brewing mash, the enzyme can be affected by polyphenols present in the mixture. Our aim was to evaluate the kinetics and equilibrium of the interaction of α-amylase with some polyphenols (chlorogenic, caffeic, ferulic ac
Quím. Nova. Publicado em: 2017-08
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4. Aminonaphthoquinone Mannich Bases Derived from Lawsone and Their Copper(II) Complex Derivatives: Synthesis and Potential Cholinesterase Inhibitors as Identified by On-flow Assay
A new series of Mannich bases derived from 2-hydroxy-1,4-naphthoquinone (lawsone), substituted benzaldehydes and two primary amines, and their Cu2+ complexes were synthesized and evaluated for their potential as selective cholinesterase inhibitors (ChEIs). Immobilized capillary enzyme reactors (ICERs) bearing butyrylcholinesterase (BChE) and acetylcholineste
J. Braz. Chem. Soc.. Publicado em: 2016-03
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5. Potentiometric Titration and Out-Of-Equilibrium pH Response of the Biotite‑Water System
Minerals in soils contribute significantly to the capacity of soils to buffer pH disturbance. In this paper, we present the pH buffering capacity of a common soil phyllosilicate mineral, biotite. We performed equilibrium potentiometric titrations and we also monitored the pH response kinetics of the mineral-water system in order to develop an out-of-equilibr
J. Braz. Chem. Soc.. Publicado em: 2015-09
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6. Adsorption of Transition Metal Chlorides by Silica with Grafted 1-n-Propyl-3-Methylimidazolium Chloride
Silica with grafted 1-n-propyl-3-methylimidazolium chloride was investigated as adsorbent for the removal of cobalt(II), copper(II), zinc(II), cadmium(II) and mercury(II) chlorides from alcoholic and aqueous solutions. The adsorption proceeds via the formation of metal-chloride anionic complexes detained near the grafted organic cations as counterions. This
J. Braz. Chem. Soc.. Publicado em: 2015-06
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7. Evaluation of Chemical Equilibrium and Non-Equilibrium Properties for LOX/LH2 Reaction Schemes
ABSTRACT: Nine chemical reaction models for equilibrium schemes and six chemical models for non-equilibrium ones are studied, considering different conditions found in real liquid oxygen/liquid hydrogen rocket engines. Comparisons between two eight-species models have shown that the most complex is the best one. Besides, it was also verified that the most co
J. Aerosp. Technol. Manag.. Publicado em: 2015-03
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8. Solubility measurement and solid-liquid equilibrium model for the ternary system MgBr2 + MgSO4 + H2O at 288.15 K
The solubility of magnesium minerals and the refractive index of the ternary system MgBr2 + MgSO4 + H2O at 288.15 K were investigated using an isothermal dissolution method. It was found that there are two invariant points in the phase diagram and the solubility isotherm of this ternary system consists of three branches, corresponding to equilibrium crystall
Braz. J. Chem. Eng.. Publicado em: 2014-06
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9. Equilibrium studies of 2,2'-(5-bromo-6-methylpyrimidine-2,4-diyl)bis(azanediyl)dipropanoic acid with some transition-metal ions in aqueous solution
The stability constants of the 1:1 complexes formed between M2+ (M2+: Mn2+, Ni2+, Cu2+, or Cd2+) and BMADA2- (BMADA: 2,2'-(5-bromo-6-methylpyrimidine-2,4 diyl)bis(azanediyl)dipropanoic acid) were determined by potentiometric pH titration in aqueous solution (I = 0.1 mol L-1, NaNO3, 25 °C). The stability of the binary M - BMADA complexes is determined by the
Quím. Nova. Publicado em: 2014-06
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10. Ab. initio study of the structural, elastic, electronic and optical properties of Cu3N
Electronic, optical, elastic, properties of Copper nitride (Cu3N) in cubic anti- ReO3 phase have been studied using the full-potential augmented plane waves (FP-LAPW) within density functional theory (DFT) framework. Generalized gradient approximation (GGA), local density approximation (LDA), Perdew - Burke - Ernzerhof generalized parameterization of gradien
Mat. Res.. Publicado em: 01/04/2014
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11. Solid-liquid stable phase equilibria of the ternary systems MgCl2 + MgB6O10+ H2O AND MgSO4 + MgB6O10 + H2O at 308.15 K
The solubilities and the relevant physicochemical properties of the ternary systems MgCl2 + MgB6O10 + H2O and MgSO4 + MgB6O10 + H2O at 308.15 K were investigated using an isothermal dissolution method. It was found that there is one invariant point, two univariant curves, and two crystallization regions of the systems. The systems belong to a simple co-satur
Braz. J. Chem. Eng.. Publicado em: 2014-03
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12. Kinetic, thermodynamic properties, and optimization of barley hydration
The hydration kinetics of five barley cultivars was studied at six different temperatures ranging from 10 to 35 ºC for 32 hours applying the Peleg model. Response Surface was used to describe dynamic of the process and identify the hydration time for each cultivar. The activation energy (Ea), enthalpy (ΔH*), entropy (ΔS*), and Gibbs free energy (ΔG*) wer
Food Sci. Technol. Publicado em: 2013-12